The invention relates to a method in the process of reeling a paper web, wherein
the paper web is continuously reeled around an exchangeable reeling core rotating with respect to the frame of a reel-up applying the reeling process,
the paper web is guided to a reeling core via a roll assembly
a first press device arrangement is arranged to move with respect to the frame of the reel-up,
by means of the first press device arrangement a first nip contact is maintained to the paper web formed on the reeling core, and the first press device arrangement is transferred with respect to the frame of the reel-up, and
by maintaining the first nip contact established by means of the first press device arrangement, the paper reel formed on the reeling core is brought into a second nip contact with a second press device arrangement.
The above-presented method in the reeling process for a paper web is disclosed in the publication EP-792829. In this publication, the first press device arrangement as well as the control roll assembly of the paper web, especially the final part of the same, is connected to a carriage moving in the machine direction, wherein the first press device arrangement is utilized to maintain a nip contact to the paper reel that is being formed, and said paper reel is transferred in the machine direction in contact with the second press device arrangement, which participates in the process of stopping-the full paper reel. The construction applying the method is relatively complex and heavy, because it is difficult to move the carriage and the roll assemblies to be connected thereto. Furthermore, the adjustment of the intensity of the nip contact is especially difficult in such a combination of devices.
The purpose of the invention is to introduce an improvement to the problems in the method of prior art, thus enhancing the state of art prevailing in the field. To attain the above-presented objectives, the method according to the invention is primarily characterized in that
in a manner known as such, the section of the roll assembly before the first press device arrangement and the first press device arrangement are established as separate units,
in a manner known as such the paper web is guided via a roll assembly which is arranged stationary with respect to the frame of the reel-up immediately into a nip contact in the first press device arrangement, and
the paper reel that is being formed and the first press device arrangement are transferred as a combination in the travel direction of the paper web in a position controlled manner.
The publication DE-29811053 U1 discloses a reeling up method, in which the first press device arrangement and the roll assembly are established as separate units, and in which the roll assembly is arranged stationary with respect to the frame of the reel-up. However, in this publication the distance between the last roll of the roll assembly and the first nip contact is kept constant during the entire reeling up process. Thus, it is not possible to attain the advantage which is attained when the distance between the first nip contact and the last roll of the roll assembly grows in a position controlled manner, (i.e. the position of the paper reel that is being formed is altered in the machine direction in accordance with a predetermined control manner (continuous and/or discontinuous) e.g. according to the diameter) when the paper reel that is being formed and the first press device arrangement are transferred as a combination in the travel direction of the paper web.
Thus, the method makes it possible that the paper web that is being formed can be transferred in the machine direction in contact with the second press device assembly establishing the second nip contact, so that the first nip contact is maintained, wherein the first press device arrangement can be returned to the reel change station, to which a new reeling core is brought from the reeling core storage, and the end of the paper web is cut and the reeling is started on a new reeling core. Because only the first press device maintaining the first nip contact is transferred in the machine direction together with the paper reel that is being formed, the construction is light in weight and it is easier to control the strength of the nip contact.
Furthermore, another advantage attained by means of the invention is the improved control of the nip load. In the method according to the invention, the first nip contact is utilized to control/establish a so-called reeling nip, by means of which the quality of the paper reel is affected substantially. In the method the first press device arrangement is thus loaded against the reel that is being formed. Advantageously, in the method the direction of this loading force deviates substantially (advantageously 60xc2x0 to 120xc2x0) from the travel direction of the paper reel that is being formed when it is transferred in a position controlled manner.